Conjunctivitis, a sinister culprit of the realms of ocular infections, spares no one and spreads like wildfire. Conjunctivitis, commonly known as pink eye, is an utterly uncomfortable and severely contagious ocular infection. Both bacteria and viruses can infect the eyes, but viruses are behind the majority of the infections. However, allergens and irritants can also initiate inflammation, causing teary and irritated eyes.
Causes of Conjunctivitis
Most of the infections are caused by viruses. However, bacteria can also be the reason behind it. Sometimes, allergic conjunctivitis can also occur—allergens like pollens and animal dander cause allergic conjunctivitis. Unlike viral or bacterial conjunctivitis, allergic conjunctivitis is not contagious.
Types of Conjunctivitis
There are three types of conjunctivitis on the basis of microorganisms that cause this infection.
Viral Conjunctivitis
Viruses cause the majority of cases of conjunctivitis. Such as:
1: Adenoviral keratoconjunctivitis or epidemic conjunctivitis is a term for conjunctivitis caused by adenoviruses. Adenoviruses are a group of viruses that mainly cause the common cold but are also reported to be the primary pathogens behind inflamed conjunctiva. Approximately 65 to 90 % of cases came under the name of adenoviruses.
2: Herpetic Conjunctivitis is another severe infection caused by Herpes simplex viruses. Similarly, there are other viruses, such as enterovirus 70 and Coxsackie virus, that are responsible for causing acute hemorrhagic conjunctivitis. These viruses were first isolated and identified in 1969 in Ghana and have been reported to cause numerous worldwide epidemics since then.
Bacterial Conjunctivitis
Staphylococcus aureus, Streptococcus pneumoniae, and Haemophilus influenzae are known to cause acute bacterial conjunctivitis; however, Moraxella lacunata, Chlamydia, or Gram-negative enteric flora are responsible for causing chronic cases of conjunctivitis. Chlamydia is the least common cause of chronic bacterial conjunctivitis. Few bacteria like Neisseria gonorrhoeae, β-hemolytic streptococci, and Corynebacterium diphtheriae cause hyperacute conjunctivitis, which is marked by pseudomembranous covering the conjunctiva. The grouping of white blood cells gives rise to the formation of loosely attached pseudo membrane.
Allergic Conjunctivitis
Various allergens or irritants like pollens, smoke, perfume, cosmetics, dust mites, shampoo, or pool chlorine induce this infection. Apart from viral conjunctivitis being the primary cause of ocular disease, allergic conjunctivitis impacts 15 to 40% of the population.
Transmission of Conjunctivitis
The spreading of conjunctivitis differentiates between contagious and non-contagious conjunctivitis.
Contagious Conjunctivitis
As viruses and bacteria are living organisms, conjunctivitis or pink eye disease is highly contagious, meaning that the infection quickly spreads from one person to another due to the transmission of these microorganisms to healthy persons. Notably, person-to-person transmission has been identified in case of viral or bacterial conjunctivitis. Their common ways include direct contact through touching one’s infected eyes or sharing objects infected persons use.
Non-Contagious Conjunctivitis
No conjunctivitis has been reported caused by allergens being transmitted from one person to another. This may be attributed to the non-infectious nature of allergens because they directly involve our internal body’s immune system.
For instance, some people naturally resist certain environmental particles like pollen. Whenever they come in contact with such particles, an unnecessary and exacerbated immune response is generated in their bodies against these particles. In this case, conjunctivitis primarily occurs due to internal body disturbances rather than some infectious agent like microorganisms. Therefore, conjunctivitis caused by allergens cannot spread from one person to another.
Note: Only the infected individuals are the primary reservoir and transmission source of infection until the disease symptoms are present, which may last for a week or two.
Signs and Symptoms of Conjunctivitis
If you are experiencing any one symptom from the below list, it means you have Conjunctivitis or pink eye disease.
- Redness of white of eyes and inner eyelids
- Excessive tearing
- Itchy and irritated eyes
- Photosensitivity is another primary symptom of conjunctivitis
- Swollen and gritty eyes
- Greyish or yellow discharge from eyes caused by the production of pus is associated explicitly with bacterial conjunctivitis.
- Feelings like the eye is an external part of the body
This disease is classified into three types based on pathogens that are the cause of conjunctivitis; these show different signs and symptoms such as:
Symptoms of Viral Conjunctivitis
Symptoms of viral Conjunctivitis include cold, flu, respiratory problems, and water discharge from the eye, and the main symptom is that it spreads from one eye to another within days.
Symptoms of Bacterial Conjunctivitis
The infection affected by bacteria shows the discharge of pus from the eye, which leads to the sticking of eyelids; sometimes, it occurs with an ear infection.
Symptoms of Allergic Conjunctivitis
This infection occurs in both eyes; itching, tearing, swallowing of eyes and nose, sneezing, and asthma are the main symptoms associated with allergic conjunctivitis.
Diagnosis of Conjunctivitis
Ophthalmologists quickly diagnose this infection’s real cause in a step-by-step process:
- They will first observe the patient’s symptoms and ask general questions like previous allergic, viral, or bacterial infection history.
- Then, they may ask for acuity or eye vision checking tests if they suspect low vision or loss of vision.
- Sometimes, your healthcare provider may ask for a swab test if the disease symptoms are difficult to diagnose. In this test, a thin swab is moved around your eyes to soak it with eye secretions. It is then sent to the lab for culturing to diagnose bacterial causes of conjunctivitis. This test benefits antibiotic selection, especially if previously prescribed antibiotics are ineffective in treating this disease.
- Similarly, viral culturing may also be suggested to diagnose the viral cause of conjunctivitis. In contrast, diagnosing allergic causes of conjunctivitis is not possible through culturing. For this purpose, a specialized patch test is recommended, which involves the identification of specific substances causing allergic inflammation.
- Only rarely, fungal or chlamydial infections may also be responsible for conjunctivitis. In this case, doctors ask patients to undergo conjunctival scrap extraction for cytological analysis of ocular disease.
Treatment of Conjunctivitis
Like diagnosis, treatment of conjunctivitis also depends on whether allergens or pathogens like bacteria and viruses cause it.
Treatment of bacterial Conjunctivitis
Bacterial Conjunctivitis is usually treated by prescribing antibiotics through tablets, eye ointments, or drops. Some parents feel it tricky to put ointments or eye drops if their children are infected. In this case, it is enough if the drop or ointment sticks with the eyelashes as it can easily melt into the eyes from there.
Fluoroquinolones, sodium sulfacetamide, or trimethoprim/polymyxin antibiotics are commonly prescribed for up to seven to ten days to treat bacterial conjunctivitis.
However, not all patients are treated by initial antibiotic therapy. Therefore, they must require a bacteria-specific culturing test to diagnose the specific bacterial cause of their conjunctivitis or to identify whether the infecting bacteria are antibiotic-resistant.
Viral conjunctivitis recovery
Viral conjunctivitis typically recovers on its own and does not require any medication; however, antihistamines like diphenhydramine are recommended to relieve symptoms.
Allergic conjunctivitis treatment
Cool water and artificial tear therapies are suggested in mild cases of allergic conjunctivitis. Cool water is poured on the face in an inclined position to mitigate itchy and burning sensations. Nonsteroidal anti-inflammatory drugs and antihistamines are prescribed in severe cases.
Prevention of Conjunctivitis
- Avoid touching or rubbing infected eyes.
- Ensure hand hygiene by adequately washing hands with soap and water.
- Avoid sharing personal items like contact lenses, makeup, cups, or towels.
- Change pillow covers often
- Do not use old eye makeup
- Don’t share your towels
- Newborn babies may also experience bacterial conjunctivitis; this bacteria comes from the mother. It may appear as an ophthalmia neonatorum in infants, but mothers do not exhibit any symptoms of this infection; that’s why an antibiotic ointment is applied to every newborn child to prevent this disease.
Final Thoughts
Conjunctivitis, also known as pink eye, is an infection of the thin, clear tissue of the white eye that lines the eyelid. Pathogens and fomites that usually cause it include bacteria, viruses, and allergens, which lead to redness, itching, and increased tearing of the eye. It can affect people of any age or gender. Conjunctivitis dates back to Egypt, where it is described in medical texts.
Frequently Asked Questions – FAQs
How long does dengue fever last?
Dengue shows symptoms like fever and could last for 2 to 7 days. When an infected mosquito bites a person, dengue fever occurs after an incubation period of 4 to 10 days.
Which antibiotic is best for dengue fever?
There is no specific medicine for this disease. You can use some pain relievers according to your doctor’s prescription.
How can I examine dengue?
A molecular test is recommended, which checks the dengue virus in your body; PCR is a type of Molecular test.
About the author
Dr. Madilyn Adams has a Ph.D. in molecular medicine from Harvard University and has been working as a medical blogger for seven years.
References
- https://www.cdc.gov/conjunctivitis/about/symptoms.html#:~:text=Symptoms%20of%20conjunctivitis%20
- https://www.mayoclinic.org/diseases-conditions/pink-eye/symptoms-causes/syc-20376355
- https://my.clevelandclinic.org/health/diseases/8614-pink-eye
- https://aao.org/eye-health/diseases/pink-eye-conjunctivitis
- https://www.ncbi.nlm.nih.gov/books/NBK541034/
